When people ask me how smart my dog is, I say that she has about the intelligence of a toddler. Chaser is a 9-year-old border collie who knows 1,000 words, but any dog is potentially capable of reaching toddler-level cognition and development, including learning the basic elements of language.

Thanks to her language learning, Chaser has been called “the most scientifically important dog in over a century” by Duke University animal-intelligence researcher Brian Hare. Language learning is an interesting test of animal intelligence because it requires unconsciously grasping a series of concepts in much the same way that children do as they advance from wordless babbling to complete sentences. For me, the most crucial common characteristic of dogs and toddlers is that they both learn best through play. I made games and other playful interactions with Chaser the basis of an ongoing conversation, speaking to her throughout the day in simple words and phrases just as I would to a toddler. Our language games revolved around finding, chasing, fetching and herding her toys — behaviors that released her instinctive drives as a border collie. Instinct-based play gave the toys value in Chaser’s mind, and that in turn gave value to the words — proper nouns and common nouns, verbs and even prepositions, adverbs and adjectives — I spoke to her in connection with the toys.

Chaser’s first conceptual breakthrough came when she was 5 months old when she realized that objects like her toys could have unique names. Like a young child, she also grasped the referential cues — my holding up a toy and pointing to it while saying its name — that enabled her to map a particular word to a particular object (called “one-to-one mapping” by language-learning researchers). That learning opened the door to a succession of concepts. Chaser learned that nouns and verbs have independent meanings and can be combined in many different ways (combinatorial understanding). She learned that a single thing can have more than one name, like a favorite stuffed animal that can be identified both by a unique proper name like Franklin and the common noun toy (many-to-one mapping). She learned that a single common noun, like stick or car, can identify several different things (one-to-many mapping). And she learned to reason by exclusion, meaning that she can identify a new object she’s never seen from among a group of familiar objects simply on the basis of hearing its name for the first time (drawing an inference). She achieved all of this learning, including knowing the proper-noun names of over 1,000 stuffed animals, balls and Frisbees in her first three years.

Creative, conceptual learning builds on prior learning in an open-ended way. Most recently, Chaser has learned to successfully interpret sentences with three elements of grammar (“To ball, take Frisbee”) and a semantic reversal (“To Frisbee, take ball”). And I am using verbal and visual cues to enhance her ability to learn by direct imitation of me and to match to sample.

Learning by imitation — I tell Chaser, “Watch what I do. Now you do it” — requires her to have the conceptual understanding, conscious or unconscious, that I want her to copy my behavior. When toddlers grasp the concept that we want them to imitate us, science says that they are demonstrating an implicit theory of mind and understand, unconsciously, that another person has a unique point of view different from their own. Matching to sample — I hold up an object, like a shoe or a ball or a stuffed teddy bear, and ask Chaser to find another one — is also an abstract conceptual challenge; it requires understanding, “I’m supposed to find something that has the same characteristics.” This, too, is a signpost in toddlers’ cognitive development.

Like toddlers, Chaser and all other domestic dogs understand human pointing, more evidence that they have an implicit theory of mind. It is fascinating that in addition to dogs, elephants also seem to understand human pointing, whereas our closest animal relatives, chimpanzees and bonobos, do not. (Chimpanzees, bonobos and other primates have demonstrated implicit theory of mind in other ways.) These disparate findings show that science has a long way to go before it can say exactly what constitutes intelligence in any species, including humans.

Science is finding increasing evidence of creative problem solving, together with a propensity for play, in animals as diverse as crows, parrots, dolphins, dogs and primates. We are nowhere near being able to rank these animals in a hierarchy of intelligence, but dogs seem to be particularly good candidates for language-learning experiments because of their shared evolutionary history with humans and their unique interspecies social relationship. The greatest misconception about animal intelligence is that animals and humans have completely different kinds of minds. Through play, however, Chaser continues to learn things that were once thought to be possible only for humans, demonstrating that our minds and dogs’ minds are much more alike than we think and differ much more in degree than in kind.

John W. Pilley is an emeritus professor of psychology at Wofford College. Chaser has been a member of his family since 2004, and he has published the findings from their work in the journals Behavioural Processes and Learning and Motivation. The views expressed are solely his own.

Pilley is the author, with Hilary Hinzmann, of Chaser: Unlocking the Genius of the Dog Who Knows a Thousand Words (Houghton Mifflin Harcourt).

Science says that dogs only see in black and white because they do not have receptors for color vision. Have you used any words for colors that the dog could recognize to identify the color? Nature will find a way to do things we have believed to be impossible. This could be a way to verify their color blindness or see if they do see colors. Their brain may do it differently than ours and wouldn't be explained as if they are human. Of course different colors would be different shades of gray in black and white but there could be some tests used to check if they are identifying the shade of gray if different colors could be made to be the same shade of gray but yet we would clearly know if it is red or black or what ever colors are used.

Interesting. My aunt and uncle's dog is not a border collie (she's a mutt of some sort-- they're not entirely sure what's in her), but she's far and away the most intelligent dog I've ever known. The last time I was visiting them, my uncle was just talking to the dog normally, as if she were human. She really looked like she was listening, and even let out this weird, exasperated-sounding growl noise when he started talking about something that annoyed him. Then, he told her to go get her blue ball (and she's got an entire box of toys, including several different balls!), and she instantly when and dug through all of them until she found the blue ball. They played with it for a while, until my uncle wondered out loud what my aunt was doing, and he told the dog to go check on her. She did! I was utterly amazed, and I asked my uncle how many words she knew. He just shrugged and said they haven't really been counting-- they just talk to her, and she seems to understand most of what they say. I don't think they realize what an exception their dog is :)

My opinion about animals despite being innocent, if any of them can perform any art or fun even somewhat lessthan a human baby can do, deserves more credit than a human adult would get inspite of being amongst the most intelligent one.

I am not at all comfortable with scientists holding animals captive in laboratories, so that these men and women can study the animals' intelligence, communication skills, etc. People teaching their dogs is another reality altogether. Keep the chimps and parrots and dolphins in the wild, where they belong.

this article is amusing. dogs have learned our 'language' centuries ago. they know our facial expressions and sounds we make because they are connected to us internally. a dog is more like a medium or a psychic than actually mimicking us. however, the mirroring effect is part of how they learn from each other and learn about us as well. they have an innate ability to connect with us in ways we will never be able to explain. they are smarter than any toddler and to equate a dog to a human baby and how we learn is inadequate to me. this scientist could think the dog is picking up on actual words, but i believe they are picking up on our intention, our thoughts our energy and frequency. being a canine behaviorist and working with dogs for over 10 years now, I have seen this innate ability from dogs that have not been in a lab for 9 years. all types of dogs, all sizes, breeds, etc. some, of course, are smarter than others, like humans; but they are all sentient beings that are more mystical than actually understood by us. there is a segment on a doberman that a woman rescued. this dog puts his toys in order by what type they are and their colors and making shapes with all the toys in totality! it is amazing to watch. the human did not train this dog, this dog did this on its own. there are dogs that can smell dis-ease in a human body, like cancer. this was not taught to the dog. just an example of why i think this research is less than enlightening.

Irene Pepperberg used a similar technique to teach basic language to her African Grey parrot Alex.

For years people who have kept pets have understood that these animals have a much finer understanding of human language that conventional science would admit. Now at last Science is catching up so hopefully animals will get much more respect in law.

All joking aside, my GSD can read thoughts, there were 2 distinct instances in which a friend walking behind the dogs said a comment that "kelly had to put her dog to sleep" and the GSD became agitated, mad, suspicious and kept looking back at her, and wouldn't let her get near all day, even though they were common walking partners. Of course, he knows the word "sleep" but not in the context of "kill the dog" but somehow, without and visual clue, no body language (which they are great at) he knew what she meant, that is weird.

Then just last month, my dad was over playing with the dogs, having fun all around, and then my dad mentioned a neighbors dog had to have euthanasia, and instantly the GSD barked at him, backed away, stopped playing and went to watch him from a distance. Dad instantly understood the dogs reaction and he said "Wow you have to be careful what you are thinking around here, cause obviously he doesnt know the word euthanasia"

I am proud of Mr Pilley's work displayed here and inspired by the findings. My personal interest is in how service dogs can help disabled veterans in a psychological sense as much as they already do for the physically disabled.

I can only hope that such brilliant minds such as John's (and, indirectly, Chaser's) are not affected too negatively by the way humans with a keyboard and the ability to repeat concepts they don't even understand decide to provide commentary that would make even a dog question the average American human's ability levels of intelligence let alone common human decency.

I have a 14.75-year-old Pomeranian who had a near-death experience in June of 2013 and has either lost much of her vocabulary or has chosen to ignore it, but before that she knew 205 toys by name, 24 colors and 50 commands. I could tell her, from the living room, to "Go in the bedroom and get the orange ball" and she would. Like Chaser, she learned the names of some toys by inference. But her 205 is nowhere nearly as impressive as marvelous Chaser's 1,000.

I also think that all dogs are more intelligent than we give them credit for but that some breeds don't share the degree of intelligence of a breed like a border collie (or a Pomeranian).

"It's often used to power animal rights agendas" - Melissa, please provide your sources; otherwise you come off as a paranoid carnivore who seems afraid of the notion of intelligent life other than human. Your dog , "possibly a German Spitz" should watch his back - apparently you wouldn't think twice about having him for Sunday dinner.

I tried doing this with my dog but then I realized that I could not keep track of the names of very many toys. For example, if I called the blue stuffed bear 'Bear' and the pink stuffed bear was 'Teddy' and the threadbare bear 'Theo,' the next time I'd forget which was which. Clearly this dog has a better memory than I do.

But he does know that everything in his two baskets of toys are called 'toys' and he never mistakes the very similar stuffed critters that belong to my grandson as his toys.

@MelissaS The
author said, "all other domestic dogs understand human pointing." This
statement is a rather well-known fact among animal trainers, let a lone
animal intelligence researchers. I do not see how or why you concluded
the author is "stupid" for saying this. In fact, your post gives the
impression you are a jealous teenager, angry that your dog can't do what
his dog can do. Or, a mother angry that his "child" is smarter than
yours. I'm not sure what's going on with your post, except that it is
beneath the author, and the science.

Number one, border collies are a breed of dog that have been selectively bred for this type of human-directed work. Not much that has been presented here is so unusual from their traditional position of being out working sheep. The author shows his stupidity by suggesting that all dogs are capable of this, it simply isn't true. My dog, possibly a German spitz, would NEVER be able to do the same work as border collies. Still, a dog is a dog. None of them begin to approach a human level of intelligence, period. There are many people who immediately interpret any form of intelligence within animals as a sign of comparable human intelligence or even superiority because that's what they wish to see and that's the hypothesis they're riding on. It's also often used to power animal rights agendas. There's a lot more to a toddler 's mind over deciphering object-oriented words and some extremely basic syntax, but people doing this type of work just seek to elevate the animal's status in every aspect while downplaying what makes humans exceptional.

@Kathyn- Donnie the Doberman Genius - I remember that episode on NatGeo - I wish they had shown objective footage of him putting the toys face down or touching hands. Definitely worth the few minutes to watch the video...

@SteveLane I house sat for a friend of my dad's a couple yrs ago whose parrot would randomly repeat the owner's side of telephone calls - pausing between phrases just like he heard them: 'Hello - Good, thanks - Yep, sounds good -' a whole series of different calls. I asked the owner when he returned and he said, "Oh yeah, it's cute at first..."- until he repeated the ex wife's name while a current girlfriend was there one day. LoL

@guitargyl Uh yeah... I'm a police officer, and I would only harm a dog if it was attacking others. I have a dog myself you know, and many of the people I work with also own pets. We cops are people too, and the majority of us don't ever want to kill anyone, be they human or animal. Gasp! What a concept!

@guitargyl I love dogs and would never shoot one unless it was harming a child or a defenseless person. i was acop for 30 years, and would rather shoot a person then a dog. not all cops get off on shooting dogs I never met one in 30 years.

@guitargyl - And claim the dog was attacking him, and was forced to shoot because he was "in fear of his life" - even when a video shows a fleeing dog being shot or the cop chasing after a dog to shoot it in a different room. Indefensible.

@MichaelFaust This is a question I want to direct to the people involved with Chaser too. Science says that dogs only see in black and white because they do not have receptors for color vision. Have you used any words for colors that the dog could recognize to identify the color? Nature will find a way to do things we have believed to be impossible. This could be a way to verify their color blindness or see if they do see colors. Their brain may do it differently than ours and wouldn't be explained as if they are human.

@MichaelFaust I would like to know how you taught your dog 1250 words, and how the dog indicates that it knows the words. I have a 16-year-old Wheaten Terrier, as a breed said not to be as bright as a GSD, who nonetheless knows around 1400 words. This is acknowledged by others, including my husband. He signals to me by licking or not licking his nose or by choosing a left or right hand. Also, what sorts of words does your dog know. Some of the words my dog knows are pretty sophisticated, much beyond what would be expected of a toddler, more like a 5-year-old.

@mimbrava The article says Chaser knows 1000 words, not the names of a thousand toys. So, "Go into the bedroom and get the orange ball" is six words (not counting "and" and "the"), and you're probably only counting "orange ball." Congratulations on your very clever dog. Her knowing so much is indicative of a wonderful partnership. I hope she recovers.

@NavyMom21 Your comment is insensitive and mean spirited. Should I construe that to mean you always are, or accept that you generally are a nice person, but were offended by Melissa's opinion? It is possible to disagree without being insulting and making huge assumptions about the other poster.

@MelissaS Help me out, because I may have missed something. Did anyone besides you suggest that dogs should be enrolled in kindergarten? Did anyone besides you ever suggest that your dumb dog would be as smart as mine?

@MelissaS "author shows his stupidity" by making claims he did not make. I'm sure this Duke University researcher does not think, and did not claim, that dogs or any other non-human animal have brains just like humans. He only analysed the ways a dog can perform some of the same types of thinking as young humans. Too bad he's not on this string to explain the things about his research and conclusions you choose to misunderstand.

@MelissaS His stupidity????.. How many college classes have you taught? Only person showing their stupidity here is you. Try wording your insult a little differently next time. Professor Pilley is a highly educated man. You may be a dog owner but you are obviously no expert. Maybe you just aren't smart enough to teach your old dog new tricks.

@MelissaS I don't think the author did this at all, and to call him stupid is very condescending and arrogant of you. He is merely pointing out that this dog can do some if the things a toddler can do with basic language. He never said he approached a level of human intelligence. Dogs are remarkable creatures, and can do many things humans can not. For example they are extrememely sensitive to body language and facial expressions in humans, and can perceive their masters moods by picking up subtle clues in posture, gait, etc, than even other humans cant.

Intelligence has many asprects to it, and of course no dog can come close to a human. But they do have an intelligence of their own, and should be respected for it.

@steverhumphries55@MichaelFaust Sorry to disappoint. But with my experience with two dogs to whom I have taught hundreds of words, they have trouble discriminating color. Dogs are not completely blind to color, according to current science research. They see some color but it is muted and they would have similar problems discriminaing color as a human who is "color blind." The first dog, who knew about 800-900 words did not seem to understand the concept. The second dog, who is definitely a bright dog and knows things like shapes (round, square, flat, circle, etc.) seems to understand but often fails tests of his knowledge of color. So, dogs have some receptors for color, but according to my findings they do not have enough to see like humans do.

@valkyries.valhh@AmyKendrick I had a dog that could do that. He would go nuts when we mentioned the word "walk". He would run to the hall tree and grab his leash, even when we weren't planning on going for a walk. So we started spelling it. It took about two times before he figured out what the letters meant.

We could also tell him to "go get the ball" or "go get the toy", or other things and he would go and get the correct object. On one occasion he ran into the next room and couldn't find the toy so he came back with an obvious question on his face. I told him "it is up in Mary's room". He ran up the stairs to Mary's room and brought the toy back. There was no actual training involved in this. He picked it up just from listening to ordinary conversation that was not directed at him.

@kj72font That's right, for someone so highly educated to make a nonsensical statement like he has is ALL THE MORE REASON to question his credibility. I do not need to be an 'expert' to use common sense. You also need to take a stab at using your own brain instead of having the 'experts' think for you. I have stated well-known facts about border collies and other breeds. Perhaps this person should try and impress us with other dog breeds, such as bulldogs and Afghan hounds. Do not grab a border collie and use that as a representation for all dogs.

@jimmoirRead this again: "When people ask me how smart my dog is, I say that she has about the intelligence of a toddler." Glad we are on the same page about what dogs are capable of, but you seem to lack basic reading comprehension.

@davej1s@MelissaS Nobody said dogs were just as intelligent as their owners. In many cases [empirical evidence gathered at the local dog park] they are in many cases smarter. There is plenty to disdain humans for---greed, lying, theft, adultery, war, self-centeredness, and on and on. Show me a dog that possesses any of these characteristics, or for that matter, any other animal.

Our dog learned that O U T meant the same as out, as well as letters for words like treat, car, and food. She also learned that she was the D O G.

We noticed that she would get very excited when she heard the word "want." It dawned on us that she had learned that word in phrases like "want a treat?" and "want to go out?" So we'd ask her, "What do you want?" and she'd run to the door, the pantry, etc. to show what she wanted.

@kj72font So you called me stupid and expect me to apologize? That's OK, I can take what I dish out, because I'm prepared to defend it. I think the author is stupid if he believes that dogs possess the same intelligence as toddlers, period. This claim lacks insight into the human condition and instead is serving the cartoony mindset that is fashionable these days that non-humans are secretly smart and we're just too self-obsessed to see it. See the replies to me if you want proof of this.

@MelissaS You may have a well educated reason for your response. That does not give you reason to call the man stupid. In fact, you would have received little to no reply from anyone had you not chosen to point out his "stupidity." Where he may have been vague in saying ALL dogs have this capability, maybe he meant ALL dogs he works with. ALL humans have the capability to reach great heights with the right teacher. Maybe instead of defending yourself to no end here, you just apologize for being "stupid" and move on.

@MelissaS@MarjorieCaldwell I think your instincts too. Your glass is obviously half empty. There are as much variations in the minds animals as there are in humans. It is still a dog eat dog world but don't you ever get tired of the taste of dog. We all share the Earth, like it or not. The ride is a whole lot better when we care for each other and the other inhabitants on this rock. Humans have not learned everything there is to know and probably never will. Animals are not humans but humans are certainly animals any way you want to look at it.